I often think of the landscape as a palimpsest. We are surrounded by evidence of human tool use and mark-making across space and time. Near 'here' there are those mysterious cup-and-ring rock carvings (on Gardom's Edge), but they also stretch across the country and are found in America and Australia too. Other markings include clear representational work like this ibex.
Reading the article it's interesting that a contribution from the 1940s is graffiti (does that make the ibex 'art' or just older graffiti?) It's probably the everyday marking of a place, like those beautiful handprints in France. But what on earth do we make of a prehistoric painting of a policeman with a gun?